Gotenk's Bio
Goten and Trunks form this new entity by the Metamoru art of Fusion, which was taught to Goku and is passed on to Goten and Trunks while Goku is back from the Other World. The fusion must occur between two beings of equal power (Trunks has to lower his power level to fuse with Goten), and is accomplished by a goofy looking, mirror-image dance. This type of fusion only lasts 30 minutes, and they must recuperate for one hour before fusing again.